1. Field of the Invention
The invention relates to a deactivatable article security label in which the deactivation function is combined with an electronic data storage function.
2. Description of the Related Art
Deactivatable article security labels are known. Such a label is described, for instance, in U.S. Pat. No. 4,567,573 to Hashimoto. It consists of a metal coil, printed (etched) on a plastic foil, and two capacitor plates on opposite sides of this foil, connected with the two ends of the coil. The coil and the thus formed capacitor constitute a resonance circuit. When the label moves through a magnetic alternating field, for instance between the pillars of a shoplifting detection system arranged at the exit of a shop, the label, if the frequency of that alternating field coincides with the resonance frequency of the label, will return a signal as a result of the resonance effect.
In the capacitor part a weakening is provided where, at a relatively low voltage between the capacitor plates, flash-over occurs between these plates. This gives rise to a permanent short-circuit, so that the label in question exhibits no electric resonance anymore, no longer returns a signal in the magnetic alternating field, and has thus been deactivated.
This category of labels has already been in use for quite some time now. In principle, the shop is the place where the label is affixed to the article to be protected. When the product is being checked out, the label is deactivated so that the passage of the buyer with the product in question through the exit of the shop does not cause an alarm to go off.
Some problems arising with this category of labels are:
1. some labels do not allow of deactivation, so that these labels have to be removed by hand; PA1 2. after deactivation, some labels become active again because the short-circuit between the capacitor plates disappears spontaneously as a result of the handling and deformation of the label; PA1 3. they are not reactivatable. PA1 either the label coming from the factory must be in the non-active state and may only be activated in the shop where a shoplifting system is present; PA1 or all shopkeepers should have a deactivation device available.
There is a development going on in the market whereby the labels are affixed by the manufacturer of the products to be protected, called `source-tagging`. This saves handling costs at the retailer's. A problem involved is that not all retailers who sell the product in question utilize a shoplifting detection system. Those who do not have one, then also do not have the possibility of deactivating a label present on the product when the product is being checked out. As a consequence, products with active labels end up on the street. This can lead to a situation where persons unknowingly carry with them a product with an active label in it. If this person enters a shop which does have a shoplifting detection system, an alarm goes off at that instant. This is in fact a false alarm which cannot be distinguished from an alarm caused by a real shoplifter, and thus gives rise to a most embarrassing situation for the person in question and for the shopkeeper.
As for source-tagging, whereby a label is integrated into the product or into the package thereof, the above means that:
The conclusion is therefore that there is a need for a label that can be activated as well as deactivated with a high degree of reliability.